In my childhood I had corrections in the stationery when I tried to ask for that card with bright colors and / or when I was going to describe some light that shone in the dark. "It's called fluorescent", of course I called it phosphorescent since I had heard some people refer to those colors in such a way.
Time went by and I never investigated that unknown of my childhood (because in reality, and the child resolved), I simply decided to tell fluorescent for those times when they corrected me, and I also thought that it sounded better. Besides, as time passed no one corrected me, I guess they also believed that it was appropriate.

But, then that moment arrived. A very wise man I know, used the term "phosphorescent".

I did not want to correct and I did not ask, but when I got home ... I forgot it again (hehe), fortunately I heard the same word on the History and Natgeo channels the same week, they refreshed my memory and I kept thinking "this It deserves an investigation. " It turns out that both words exist and fulfill different mechanisms, but the result is similar.

Basically refers to the compound that generates the brightness, because both adjectives describe materials and processes that absorb the energy of high-radiation electrons (blue or ultraviolet light) and then is emitted at a lower frequency.

They are similar phenomena because in each one it absorbs luminescence from an external source under radiation and is transmitted from its physical body in a different wave; but in the case of fluorescence, the emission of light ceases if it moves away from the focus that radiates the energy. While in the case of phosphorescence, the luminescence lasts a little longer after disappearing the source that produces it.

In many occasions we do not distinguish the fluorescence of the phosphorescence, but to be able to leave unscathed of this doubt I will describe the cases with some materials:

These are fluorescent type:

Made with the same material that makes the ink or paint that shines with ultraviolet lamps, cathode rays or X-rays. The process ends almost immediately when the energy source ceases. However, the color of the material (without light source) is usually quite striking, because they are light colors.

While these are phosphorescent types:

The stars that we buy to place on the roof is a material that gives an example to the phosphorescence, since the energy once stored can take hours to be released. These can also acquire luminescence in the dark with the absorption of other sources of light, natural or "common" bulbs, in addition to the mentioned lights.

Now, I leave a video that shows a practice:

From my Blogspot's blog in spanish (http://somatosensorial.blogspot.com/2011/06/fluorescente-o-fosforescente.html),
2009 anecdote.